---
prelude: >
    Methods in manager classes and resource classes return wrapper classes
    that wrap values returned originally.
    For example, a wrapper class for list, a wrapper class for dict,
    a wrapper class for str and so on.
    The wrapper classes have a 'request_ids' property for request IDs
    returned from Nova (nova-api). So the caller can get the
    Nova's request IDs, then output them to logs with its own request ID.
    The function to output them to the logs will be implemented
    in other projects (cinder, heat, etc.).
features:
  - Methods in manager classes and resource classes return wrapper classes
    that wrap values returned originally.
    For example, a wrapper class for list, a wrapper class for dict,
    a wrapper class for str and so on.
    The wrapper classes have a 'request_ids' property for request IDs
    returned from Nova (nova-api). So the caller can get the
    Nova's request IDs, then output them to logs with its own request ID.
    The function to output them to the logs will be implemented
    in other projects (cinder, heat, etc.).
upgrade:
  - In case that methods return a response object and body originally and
    body is None, the methods return the wrapper class for tuple as 'body'
    instead of the wrapper class for None.
    The wrapper class for None has not been added.
